Vector length error in code

Hello,

I am trying to run a simple code, and I am having a problem with vector lenght. I went back and counted all my data points and made sure each point was equal to 8.. perhaps I am missing something?

% Plot all models 1790-1860

%Malthusian Growth Model
% Time interval
% t = (1790:10:1860)';

% Previous population
Pn = [2.913 3.929 5.308 7.239 9.638 12.866 17.069 23.191]';

% Growth Rate Assumption
R = (0.349+1)';

%Malthusian Model
E = (Pn*R)';

% Discrete Logistic Model
% Parameter and intial condtions
r= (0.349);
% Carrying Capactiy 
M= 330.0; 
 
X0= 3.929;
p= [3.929 5.308 7.239 9.638 12.866 17.069 23.191 31.443]';
 
% For loop to generate seqeunce terms
for i=1:length(p)
    F(i)=p(i)+r*p(i)*(1-p(i)/M)';
end

tBegin = 1790;     % time begin
tEnd = 1860;      % time end

%Gompertz Model
% Time Interval
% a=(1790:10:1860)';
% Population
b= [3.929 5.308 7.239 9.638 12.866 17.069 23.191 31.443]';

Data = b;

k2 = 330.0;
B = log(Data(2:8,1)./k2);
A = log(Data(1:7,1)./k2);
X = A\B;
b = -log(X(1,1));

P0 = Data(1,1);
LL = zeros(8,1);
LL(1,1) = P0;
for i = 2:8
    LL(i,1) = exp((exp(-b)).*log(LL(i-1,1))+((1-exp(-b)).*log(k2)));
end

% Single Plot
% figure
% plot(Labels,Data,'b-*',Labels,PG,'r-*')
% title('Gompertz Model, 1790-1860')
% legend('Data','Model','Location','northwest')
% hold on

%R2
SST = sum((Data-mean(Data)).^2);
SSE = sum((Data-LL).^2);
R2 = 1- (SSE/SST)

R2 = 0.9816

% Beverton-Holt Model
% Parameter and intial condtions
Pe= 486.8

Pe = 486.8000

a1= 1.23065

a1 = 1.2307

b2= 2110.5

b2 = 2.1105e+03

p3= [3.929 5.308 7.239 9.638 12.866 17.069 23.191 31.443]';

% Bevholt equation
E4 = a1*(p3)./(1+(p3/b2))

E4 = 8×1

4.8262 6.5159 8.8782 11.8071 15.7376 20.8374 28.2298 38.1273

% Time Interval
% a=(1790:10:1860)';
% Population
b= [3.929 5.308 7.239 9.638 12.866 17.069 23.191 31.443]';

Data = b;

Labels2 = [1790:10:1860]';
Labels = [1790:10:2010]';

% Plot all models 1790-1860
figure
plot(Labels2,Data,'k-*',Labels2,E,'r-*',Labels2,F,'b-*',Labels2,LL,'m-*',Labels2,E4,'g-*')
title('US Population Data, 1790-1860')
legend('Data','Malthusian','Discrete Logistic','Gompertz','Beverton-Holt Model')
ylabel('Population (Millions)');
xlabel ('Years')
axis([1780 1860 0 200])
hold on

Answer 1

[Cris LaPierre]

What line is causing your trouble? I just ran the code you shared and did not get any errors.

Best to copy/paste the entire error message (all the red text) instead of summarizing it.

Perhaps you have a variable in your workspace that is causing some trouble. Try clearning your workspace (they clear in your command window and press enter) and then run your code again.

[Kailin Johnsson]

Clearing the workspace worked! Thank you!!!